The Federal Office of Civil Aviation FOCA has immediately issued a temporary ban on flights for the Ju-52 Ju-Air stationed in Dübendorf. Inspection of the wreck of the Ju-52 crashed on 4 August 2018 by the Swiss Safety Investigation Board (SUST) revealed severe structural damage to the wing spars. These could not be detected during normal maintenance and inspection. According to current knowledge, however, they are not related to the crash on 4 August. The technical investigations at the SUST are not yet completed.

Following the crash of a Ju-Air Junkers Ju-52 three-engined aircraft on August 4, 2018, the airline restarted operations on August 17 with the two remaining aircraft of the same type. Since there were no indications of general technical defects at this time, the FOCA had approved the resumption of flight operations in compliance with precautionary measures. This also included that the FOCA would announce a flight ban on new findings from the ongoing safety investigations.

Meanwhile, the first results of the investigation by the Swiss TSB were published in the form of an interim report. There is still no evidence that a serious technical problem led to the accident with 20 fatalities. The investigation of the wreck, however, revealed severe structural damage in the form of cracks and corrosion on the main spar, the supporting element of the aircraft wing, and other parts of the aircraft. This damage was hidden during normal inspections and maintenance and could only be determined from the debris.

Since the two Ju-52 HB-HOP and HB-HOS stationed in Dübendorf correspond in age as well as in hours of operation to the crashed machine, it must be ensured that both aircraft do not show this damage. Until this proof has been provided or any damage has been remedied, these two Ju-52s may not be flown for the time being.